Electrical Machines Which of following DC motors will have percentage increase of input current for the same percentage increase in torque? Shunt. Series. Differntical compound. Cummulative compound. Shunt. Series. Differntical compound. Cummulative compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3 ,5 1, 2, 3 2, 3, 4, 5 2, 3, 4 2, 3 ,5 1, 2, 3 2, 3, 4, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC Motor uses 4-point starter? DC compound motor. DC shunt motor with field weaking control. DC series motor. DC shunt motor with armature resistance. DC compound motor. DC shunt motor with field weaking control. DC series motor. DC shunt motor with armature resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 40W 60W 80W 100W 40W 60W 80W 100W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 40% 38% 60% 68% 40% 38% 60% 68% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the armature reaction results in demagnetization of centers of poles. magnetization of leading and demagnetization of trailing pole tip. magnetization of inter poles. demagnetization of leading & magnetization of trailing pole tip. demagnetization of centers of poles. magnetization of leading and demagnetization of trailing pole tip. magnetization of inter poles. demagnetization of leading & magnetization of trailing pole tip. ANSWER DOWNLOAD EXAMIANS APP
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